sexual transmission

Men who may have been exposed to the Zika virus should wait at least six months before trying to conceive a child with a partner, regardless of whether they ever had any symptoms, federal health officials are recommending.

The Centers for Disease Control and Prevention had previously recommended that only men with Zika symptoms had to wait that long. Those who may have been exposed to Zika but never developed any symptoms were told to hold off on trying to conceive for just eight weeks.

Doctors have known for some time that a man can spread the Zika virus to a woman through sex. Now officials have documented the first case in which a woman apparently infected a man through unprotected sexual intercourse.

The case occurred in New York City when a woman in her 20s returned from a trip to a country where Zika is spreading, according to a report released Friday by the federal Centers for Disease Control and Prevention.